Drill-steel retainer



Aug. 6, 1929.

J. E. RENFER DRILL STEEL RETAINER Filed March '12 Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

JOHN mnvrnn, or CLEVELAND, onro, assrenoa TO THE CLEVELAND noon DRILL COMPANY, or CLEVELAND, onro.

DRILL-STEEL RETAINER.

Application filed March 12, 1528.

The present invention is directed to improvements in drill steel retainers.

The primary object of the invention is to provide a device of this character which can be conveniently attached to or removed from the front head of a percussive drill, and when in place thereon can be operated to permit the removal of the drill steel from the front head, or can be maintained in a position to prevent the removal of said steel.

Another object of the invention is to provide a device of this character so COIlStlIlCtBd that it can be easily and quickly moved from its inoperative or operative position, the construction being such that the steel collar engaging yoke will be positively held in advance of the drill steel collar to limit the movement thereof when not striking the work, or for withdrawing the steel from the hole, as the drill is moved backwardly.

\Vhile the drawings illustrate a preferred. embodiment of the invention it is to be understood that in adapting the means to meet specific needs and requirements, the design may be varied and such other changes in the minor details of construction may be resorted to within the scope of the invention as claimed, without departing from the spirit thereof.

For a full understanding of the invention and the merits thereof, reference is to be had to the following description and the drawing hereto attached, in which-- Figure 1 is a side view.

Figure 2 is a top plan view, partly in section.

Figure 3 is a front view. Corresponding and like parts are referred to in the following description and desig nated in the several views of the drawing by like reference characters.

In the accompanying drawing 1 designates ment 5 is rounded, as at 9.

Serial No. 261,133.

It will be observed that the inner surfaces of the walls are substantially oval in contour 111 order that the points A-B, of greater di ameter thereof will be disposed transversel v of the longitudinal axis of the front head 1 The portions of the walls which merge with the enlziirgelnent 6 have their inner faces provided with transverse ribs 10 which define inner and outer longitudinally curved seats 11 and 12.

The retainer per is formed from a single length of stout wire stock and includes a drill steel collar engaging yoke 1d and side arms 15, said side arms having elongated loops 16 upon their terminals which are substantially oval shaped in order to correspond to the general shape of the inner faces of said walls. These loops are capable of contracting when the longitudinal axes thereof are shifted, and are capable of expanding after the terminals thereof have passed over the ribs 10. In order that the loops can expand and contract the terminals thereof are spaced from the terminals of the side arms, as at 1.7.

As shown in Figure 1, the free portions of the loops are engaged in the seats 11 and maintained therein by the inherent resiliency of the loops, thus holding the retainer in its operative or closed position, so that the yoke 14 will be held in advance of the collar 3 to arrest the outward movement of the drill steel when not striking the work, or to pull the drill steel from the hole when the drill is bent rearwardly. To open the retainer pres sure is exerted thereon to swing the same, whereupon the loops will contract so that the free portions thereof can ride over the ribs 10 and afterwards expand for engaging the seat 12, thus holding the retainer firmly in its inoperative or open position. Owing to the presence of the openings 17 the retainerran be swung open or closed, the swinging move ment thereof in one direction being limited by the stops 7 and in another direction by the stops 8. The beveled faces 8 of the enlargement 6 will permit the side arms of the retainer to swing in acute angular relation with respect to the longitudinal axes of the front head.

The retainer can be moved from the front head upon moving the arms 15 thereof later-- ally a sufficient distance to permit the loop 16 to disengage the walls. Obviously, to attach the retainer to the front head the arms are spread and will contract in order that the loops will be confined by the walls.

Having thus described the invention, I claim:

1. The combination with the front head of a drill, of a collared drill steel operatively mounted therein, curved walls upon opposite sides of the front head having spaced terminals provided with enlargements, certain of the enlargements having transverse ribs defining spaced seats, a drill steel retainer having its side arms provided with loops for pivotal movement within the confines of the walls, said loops having free terminals for selective engagement with the seats.

2. The combination with the front head of ,ees

a drill, of a collared drill steel operable therein, curved walls carried upon opposite sides of the front head and having spaced terminals provided with enlargements, the major diameters of the walls being arranged at right angles to the longitudinal axes of the front head, certain of the enlargements having spaced seats therein, a drill steel retainer including side arms, said side arms having their inner ends provided with elongated loops provided with free terminals, said loops being expansible and contractible in the confines of the walls for permitting the free terminals of the loops to selectively engage the seats.

In testimony whereof I afiix my signature.

JOHN E. RENFER. 

